Electric power generating plant



Feb. 7, 1933. R w GAY 1,896,356

ELECTRIC POWER GENERATING PLANT Filed Oct. 25, 1929 2 Sheets-Sheet 1 IN VEN TOR.

BY Fmze W 6% A TTORNE Y.

Feb. 7, 1933. F. w Y 1,896,356

ELECTRIC POWER GENERATING PLANT Filed Oct. 25 1929 2 Sheets-Sheet 2 L z ah 2/ 20' 5,000 I INVENTOR. F00 Wfio a 0500550 P00060097 ATTORNEK Patented Feb. 7, 1933 PATENT OFFICE FRAZER W. GAY, OF NEWARK, NEW JERSEY ELECTRIC POWER GENERATING PLANT Application filed October 25, 1929. Serial No. 402,400.

This invention relates, generally, to power plants supplying utility systems; and the 1nvention has reference, more particularly, to a novel electric power generating plant that is adapted to efficiently carry widely varying loads such as those imposed upon a utility system. i

Heretofore, when a new generating statlon is added to a utility system it has been customary to operate the same as a base load station which means that the new station is operated at full load substantially continuously and at its maximum eificiency. However, since utility systems enlarge rapidly, and as the minimum load on such systems is generally on the order of one quarter of the maximum load or even less; it usually follows that after a few years operation as a base load station, such new generating station must gradually be adjusted to serve as a peak load station. When operating as a peak load station it is frequently necessary to start and stop the major part of the station units daily. In order for such station to operate satisfactory as a peak load station it must be initially designed at great additional expense for the highest possible efiiciency at all operating loads. Equipment such as boiler blowers, fuel feeders, etc., must be adapted to be varied uniformly from a very low to a high speed. The station must in addition he provided with an expensive control system which will maintain its inherently high efliciency under widely different load conditions. When operating as a peak load station the time of loading is so shortened that the station is idle the greater part of the time, thereby adding greatly to the overhead expense 4 of the utility system.

adapted to operate substantially continuously at maximum efficiency and other units adapted to operate for short periods of time which latter units are designed for minimum capital costs rather than efficiency. Such a station when placed in service may be operated on a load cycle similar to that of the system load and its method of operation may remain substantially constant for a generation.

In my application, Serial N 0. 352,755, filed April 5, 1929, it was shown how heat energy may be stored in heated water during periods of light load and how this stored heat energy may be made available during heavy load periods by pumping the stored water to boilers as feed water, therebyrendering it unnecessary to draw steam from the boilers during heavy load periods to heat feed water.

Heretofore, it has been impossible to employ large storage reservoirs owing to the practice of storing at constantly changing storage temperatures and pressures with consequent objectionable great lineal expansion of storage reservoirs due to such changing temperatures and pressures. Thus, it has been necessary to employ a multiplicity of small reservoirs with a corresponding increase in piping, valves etc. having a great and expensive surface area for relatively small storage volume. This system rendered it substantially impossible to either charge or discharge the heat storage reservoirs efficiently owing to the constantly varying temperatures and pressures and the consequent inefficient attempts to adjust turbines to such varying conditions, for turbines are adapted to operate most efiiciently at only a definite temperature and pressure.

Another object of the present invention lies in the provision of a generating station having novel storage means adapted to store a maximum amount of heat energy per unit of storage volume, which stored energy is made available at a high and substantially constant temperature and pressure, thereby enabling easy and eflicient operation of station units.

The storage means employedconsists of huge underground metal lined caverns or reservoirs, one or more of said reservoirs beinsladapted to store hot water at a substanti y constant temperature and pressure,

3 said stored water being rendered available l 6 asupplying dry saturated steam to replace master stored and, by evfiporafiinghsigilh sto ,water upon ingtrong it i e ha-er a .s of m a. .reserapm v I l bjmt of the pre nt inven- 3 aimeme etee w s tbemw I i they operate 7 ike fim n y whileatthe'seme M n e haus steam for h ting to be furnished to the hot water i (memoir ingplflrelity of definitely i s or PH 7 ofthisinvention, not this. i re c efix me ted the followmgdg.

w A a tics f same i w e er l 'aeho Wm P w h d pted "P yah P yme g eaas boiler J to. to the reservoir pi he p b xe e d br he w wafrom sddi mtam be m the We! gf s v ,m e

. H ra se-51' eeievetieaalviegw broken away of the n0VQfl1B liIZ1C "l nehmiar. ii fihpasteemiitd f a portion of a generating plant of this invention Fig. 3 is a view similar to Fig. 2 of another portion of the power generating plant of this mvention; 70 v Fig. 4 is a plan view of still another portionof the invention; p

. Frxi e greph sh mm h dilemm b tween the amount of heat in a cubic foot of wnter and that in a cubic foot of steam at certain temperataresmnd Ff is a typical sstem load curve carried apo'werpianto this invention.

Similar characters of reference are emv wstqindieate r ww ding me refer a a v very were holler oi "IMBWQWW v ewer j, 4 m s nexet steem we gw meswem xces of 32.00 lbs.

Since the construction-of a vYell to those in M m. PM

m1 nor describedin detail.

Voilf e: qfshaft 3,,pip 4,.water pm plo y'ed in all of the bereinabove described 30 wms Fisalandzeithedram we n meral 1 signa es:

1 9% par of the pr sent i n fi voir rrwmksteedwammeu botwaterp, i 1

aadape z wate reservoir2 not g l%mtioned at a considerable distance ground level 7 and 0 use: an

chamber Senclosed w', .concre effve-llrf a a h ch its interior y lined with relatively;

steel plate 10. The reservoir-Zia erablx imbeid in bed rock: an is to retain hot water at a relatively I .2 um. nst nipre sureof' r reb ar un p e: q a e in h ot water this 11 pres-t. hlsreaer on has t 3 relat vely inexpensive metalhc shell 10 owing the ggtnfiipm ftlais reservoir at a 69.9

voir 2 can retain sure even the o .L law magi-minim wll d 'w the .reservolr ageinst normally reeflures. The te con ontinuous u rli 7 bed st am, through, e 1

t la .1. ressure W 7 15 and when this valve iso sure superheated steam flows down into reser-' voirlfi end is stored therein'to be" r required.

ere the surrounding" bed ar mumm es 2. j

0 er li adep todpliver highp ssnn P1 an val e p me 4. Asha'ftlfi connectswit pipe12, and extends downward y .inte h aro n to u Steam r e resemble which is similar in 0DStrlLctim y; to reservoir 2. A valve I'l'i's included in shaft pened, high pres;

=i gtemtsupply' main 1e T' plyrmain as masseuse .a-

' heated-duels to a. after turbines 21-22 are coupled in driving relation to generators 25 and 26. The turbines 2122 exhaust through pipes 27 and 28 to low pressure turbines 29 and 30. Low pressure turbines 29 and 30 drive generators 31 and 32 respectively.

The shaft 15 (see Fig. 1) is also connected through piping having a valve 33 therein and a shaft 34 to a nozzle head 35 positioned in the lower portion of a hot water reservoir 2. In the event that the pressure and temperature in hot water reservoir 2 should fall below normal, valve 33 may be opened, thereby causing superheated steam to be blown through nozzle head 35 into the lower portion of reservoir 2, thereby bringing the hot water of this reservoir up to the desired pressure and temperature condition. High pressure turbine 14 exhausts into a supply main which is illustrated in Fig. 3 as connected by a pipe 38 to a'turbine 39 driving a generator 40. Turbine 39 exhausts through pipe 41 into a low pressure turbine 42 that is coupled to a generator 43. Turbine 14 drives a generator 49 the output of which is connected by a cable 50 to a circuit breaker 51, constituting one of a row of such circuit breakers. Circuit breaker 51 is connected by a cable 52 to the primary winding of a transformer 53. The secondary winding of transformer 53 is connected by cable 54 to a high tension transmission line 55. Generators 25, 26, 31, 32, 40 and 43 are also connected by cables (not shown) to circuit breaker 51.

One or more furnaces, such as those described in my copending application, Serial No. 354,557, filed April 12, 1929, are preferably employed in this invention for heating metallic alloy which alloy is circulated by suitable pumps through high pressure boilers for producing superheated steam therein. Although only a single such furnace 56 and boiler 63 are illustrated in the drawings, it is to be understood that normally a plurality of these furnaces and boilers would be employed. The metallic alloy heated within furnace 56 is circulated by pump 58 through piping 59 to 62 into the high pressure boiler 63, thereby producing superheated steam in this boiler. It is to be understood that in stead of using furnace 56 and boiler 63 for producing superheated steam, any desired boiler may be used for this purpose. Boiler 63 is connected by a pipe 71 having a valve 72 therein to a supply main 73 which in turn is connected to a shaft 74 that extends do-wn into reservoir 2. shaft 74 terminates in an elbow 75 which is positioned in the upper part of reservoir 2 and above the hot water level 7 6 therein. Shaft 74 is adapted to supply saturated steam to boiler or boilers 63 at times when these boilers of themselves fail to deliver the desired rate of fiowof superheated steam.

The superheated steam produced in boiler 63 passes through a. pipe 64 containing a valve 65 to high pressure turbine 66 driving a generator 67. Generator 6'? is connected by umper cable 68 to cable 50 for supplying electrical energy to transmission line 55. High pressure turbine 66 exhausts through a pipe 77 into a turbine 79 that is coupled in driving relation to a generator 80, the output of which is conducted by jumper cable 81 to the cable line 50.

A hi h pressure feed water heater 82 of the tubular type is connected to pipe 77. Condensate formed in feed water heater 82 flows through drain pipe 83 into a pipe 84 connected to the intake of a feed water pump 85. Pump 85 delivers feed water through pipe 86, feed water heater 82 and pipe 87 to the intake of a feed water pump 88. Pump 88 delivers this feed water through a pipe 89 to a feed water heater 90 illustrated as of the jet type. Steam is supplied to feed water heater 90 from shaft 74 by way of pipe 91 and condensed steam together with the heated feed water pass through pipe 92 into pipe 125 and from thence into the bottom of reservoir 2, thereby replenishing the hot water therein.

Turbine 7 9 exhausts through pipe 93 having a valve 94 therein into a low pressure turbine 95. A low pressure feed water heater 104 of the. tubular type is connected to pipe 93. Steam condensed in a heater 104 flows through drain pipe 105 into a pipe 106 connected to the intake of a feed water pump 107. Pump 107 delivers feed water through a pipe 108 and feed water heater 104 to pipe 84. Pipe 106 connects to the hot well 109. Turbine 95 is coupled to a generator 96 the output leads of which are connected by a jumper cable 97 to the cable line 50. The fully expanded steam leaving turbine 95 passes into a condenser 98 where it is condensed by circulating water in a manner well known to those skilled in the art. The condensed steam collecting in condenser 98 flows into a pipe 100 and is conducted to the intake of a circulating pump 101 which delivers this condensate through a pipe 102 to a cold well 103. A pipe 111 connects with pipe 102 and is adapted during certain light load periods to convey cool water from cold well 103 to the intake of a. feed water pump 112. Pump 112 delivers this water through pipe 113 into the cooling chambers of the condenser 98 from whence it flows through a pipe 114 having a valve 115 therein into hot well 109. During these light load periods, the cool condensate from cold well 103 serves to condense the steam leaving turbine 95, thereby causing this turbine to work under a high back pressure since the cold well water would ordinarily be at a temperature of about 70 Fahrenheit.

In Fig. 5 there is illustrated a curve showing the difference between the amount of heat m British in acubicfootof water and in a of dry vsaturated steam of the amqtmperaturel It will be noted that the is 5 maximum between the values -11; md-000 F. and the-curve shows 1 thfltw cubic font of water within/this tem- 1.. mugs has #120,000 B. t. u. more i fiereitthu in p cubic foot of dry I y SIG-B. t. u. per pound (i. e.

1 L w Frgpiht) are total of approxi- V {265W Lt. a: When superheated ratma'fro lirlmaervoir i6 is passed throu%)h p each pomdsas' it evaporates a Mary 580 B. t. u. of'supcr- "cubie footoi such hot water will 1" ox'nnately 24,500 B. t. u. of Jeatim into steam and there V W Irgmain in reservoir2 a cubicfoot of dry in lieu of the .water dispw htfim lbs. per square inch, which of will contain approxif v t; It results therefore, in passing through I lmfl from Weir 16 by way of W-M iSB will give up superheat and milethehot water therein, and for each ofwater so volatilized' approximnr 25,000 4,o==21,o0o B. t. u. of heat will betakeu from the hot water etor'agein reservoir 2 andpassed on b vvay of'shcit as desired urmg v I 56f 4, 0

LE6 ilhst'rItesLa-fithour load curve for utility 4 rn vvhich the novel genmg plant at t inventionis adapted to outside'aid. It will be noted a a ling-the early morning Mars from 12%615 5 m; the -load is a minimum at ,oeaxwmem M6 a. m. the load tb approximately 40,000 K. W.. By n 7- e mthe load'is 76,690 K. W. Between a lo the load has risen to- 91,000 K. W. 'api'hfetweenloudlfiit drops to 58,000 ;K. W.

v l 'mln fipgnutofip. m. the load rises in sucapproximately 76,000 K. W., w iemoox. WJto' a peak of and the load thereaiter again wahowugin.thi's=-figurer I 5:11: 0 ,beilersl and63end turbines 1, 6i "Z9 are. ads ted'to operateoontinui i. capmitie eand hence at v Baring thewperiodof fmeysteue'laidskunlfitefl a. m. the power phetis perateifseas to stoma maxi- During this ief the steam from mam 14001bs. r taken stoheat feed ratet.

boilers 63 (prefierabl at inch pressure) will o pressure turbine st mfeedwaterheaters82,101anddeamm" r be taken directly by way of pipe 71, shaft It 1 and pipe 91 to heat feed water in heatertflfl; During this period turbines 66 and79-dene will be running, the valve. 94 being closed In that turbine 95 is idle. Pump 107 will pump. a large quantity of feed water at a 7 mately 180 F. from 110151611 109. M feed water heater 104 noun 7 4 be heated to substantially the perature of turbine 79 01 800" F. From I water heater 104 this a water. 8

through ipe 84 and is forced by Q through ester 82 in which, heater t w! temperature is raised to that. of the Mali?? R Q of turbine 66 or appmiumbely 4859 1. From heater 82, the iced Writer-"1mmI, through pipe 87 topump 88 which. 7 feed water through heater 90 wher in It! temperature is raised totem-131,600 F. or T? that of the hot water reservoir-.2. rFmm I heater 90 the feed water. drains by any offl pipe 92 and pipe125, into reservoir2. a Normally a plurality of duplicate compris' boilers 63 and wlmected turbigea 66, 79 an 95 would be utilized, in case the feed water may he passed through? it greater number of atafiw during its as from the feed water eater 104 of one stage i of one boiler unit to a heater104 oi the can. respondi stage of a second boiler nfiit. and so on to t e last of such units, whereupon w it will be passed back succ$sively through i the feed water heaters 82 of the higher we bine stages. Or the feed water after through the two stages of one boiler unit 1 may pass through the higher stages of other $05. boiler units and etc. i V Thus, in accordance with this inventiolt a 1. the feed water is heated in a plurality 8 stages or steps to'the temperature of the hot water reservoir during the minimum lo "0} period. During this period turbo-genetitors 6667 and 79-80 will carry the entire 1 station toad and boiler Ijrill: deliver all. of its steam atapproximately 3200 lbs. per Y square inch to the superheated steam storage reservoir 16 by way of pipe '12 and Qack My valves- 20 and 33 being-ahead. If should tend to fall in hot water storage 'f voir 2, valve 33 may be opened and super 4:. a heated steam delivered to reservoir 2 by of irpe34 and nazzleJiead 35. ,1 system load increases between I n 7 a. m. pumps 107, 85 and 88 will be slowed jv down until they handle'substantinlly one-half of the amount offeed mm viously--hamdlad,;thcreby 'eausi'ngthe 01$ put turbe-genentwik-SG to increased as to'car'ry'a greater had and turb'mie started by openingvvahei As the "system load further bel tween 7 and 8 a. In. the feed waterpumps85, 107 and 88 are shut down and with-valve 94 open, the exhaust steam from turbine 79 drives low pressure turbine at full load. Feed water pump 112 is operated to pump cool condensate from cold well 103 through the cooling chambers of condenser 98 and through pipe 114 into hot well 109. This condensate from cold well 103 serves to condense the steam leaving turbine 95 and when this condensate enters hot well 109 it will be at a temperature somewhat less than the boiling temperature of water at zero gauge 01' about 180 F. Upon a further increase in load, valve 13 is opened causing turbine let to operate and the exhaust from this turbine will pass through main 37 to turbine 39 and from thence through turbine 42 effecting the operation of generators 49, 40 and 43. During this period all turbo-generators operating are run at their rated economical load.

As the load again decreases between 10 a. m. and 1 p. m. the above cycle of operations is reversed in part. From 1 oclock on, the load again increases and turbines 14, 39 and 42 are again put in service. As the load ap proaches its peak valve around 5 oclock the valve 20 is opened causing the stored superheated steam from storage reservior 16 to flow through shaft 15, pipes 19 and 18 to high pressure turbines 21 and 22 which drive generatores 25 and 26. Exhaust steam from turbines-21 and 22 operates turbines 29 and 30, thereby driving generators 31 and 32 all of which generators supply electrical energy to the transmission line 55. As the system load again drops ofi after 6 p. m. the cycle is again reversed.

It will be noted that the boiler equipment of the novel power plant of this invention operates continuously at constant load and any portion of the steam generated which is not immediately consumed is put into heat storage either directly in the superheated steam reservior 16 or'indirectly in the hot water reservoir 2 by heating feed water in heaters 82, 104, 98 and 90. Owing to the constant load operation of the boilers, a great saving in unit installation costs is made since it is not necessary to install variable speed fans and other auxiliary equipment ordinarily required to adjust the boilers to variable loads. Also, all parts are designed and adjusted to give maximum efiiciency at the normal operating point. Increased economy is obtained by furnishing all boiler feed water from reservoir 2. Boilers 1 are supplied with feed water by way of shaft 3, pipe 4, pump 5 and pipe 6, whereas boilers 63 are supplied from shaft 3 by way of pipe 118, having valve 121 therein, deep well pump 119 and pipe 120.

Turbo-generators 6667 and 7 980 which operate continuously, are designed for maximum efliciency at relatively great cost while the remaining turbo-generators which run only part time may be designed for a slightly lower efliciency at a great saving in cost per unit capacity.

A great saving in fixed charges against unit capacity is obtained owing to the inherent ability of the boiler installation of this invention together with its associated heat storage to supply a system load with substantially twice the amount of peak energy that may be taken from ordinary power plant installations.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is 1. An electric power generating plant for supplying a variable system load comprising, steam boilers operating continuously at constant load, steam storage means connected to one of said boilers for storing steam during light load periods, turbo-generators also connected to said boiler and to said steam storage means for operating during heavy load periods, turbo-generators connected to another of said boilers and operating continuously, said last named turbo-generators consuming a portion of the energy output of said second named boiler, and heat storage means arranged to store unused portions of the energy output of said second named boiler for use during heavy load periods.

2. An electric power generating plant for supplying a variable system load comprising, bollers operating continuously at full load, turbo-generators, a hot water storage reser- .VOlI', feed water heaters operating to utilize a portion of the output of saidboilers durmg light system load periods to heat water to boller temperature and pressure for storage in said hot water storage reservoir and means for forcing superheated steam through sald stored water for evaporating said stored water for the use of said turbines during heavy load periods.

' 3. An electric power generating plant for supplying a variable system load comprising, boilers operating continuously at full load, turbo-generators, a hot water storage reservoir, feed water heaters operating to utilize a portion of the output of said boilers during light system load periods to heat water to boiler temperature and pressure for storage in said hot water storage reservoir and means for evaporating said stored water for the use of said turbines during heavy load periods, ancladditional means acting to maintain the temperature and pressure of the hot 

